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Responses of sheep to annual cycles in nutrition 1. Rôle of endogenous growth hormone during undernutrition

Published online by Cambridge University Press:  02 September 2010

N. R. Adams ,
J. R. Briegel ,
R. D. G. Rigby ,
M. R. Sanders  and
R. M. Hoskinson
N. R. Adams
Affiliation:
CSIRO Division of Animal Production, PO Wembley WA 6014, Australia
J. R. Briegel
Affiliation:
CSIRO Division of Animal Production, PO Wembley WA 6014, Australia
R. D. G. Rigby
Affiliation:
CSIRO Division of Animal Production, Blacktown, NSW 2148, Australia
M. R. Sanders
Affiliation:
CSIRO Division of Animal Production, PO Wembley WA 6014, Australia
R. M. Hoskinson
Affiliation:
CSIRO Division of Animal Production, Blacktown, NSW 2148, Australia
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Abstract

Plasma concentrations of growth hormone (GH) are elevated in sheep during undernutrition. The present study attempted to determine whether this increased secretion mediated nutritional effects on reproduction or wool growth, using sheep immunized against growth hormone-releasing hormone and given a low-quality, sub-maintenance diet. Immunization reduced plasma concentrations of GH at all times measured (P < 0·01), through reduced pulse frequency, reduced pulse amplitude, and reduced baseline concentrations. Plasma insulin-like growth factor-1 (1GF-1) was also reduced in the immunized sheep (P < 0·01). Despite this, rates of live-weight loss and wool growth were similar in immunized and control ewes. Plasma concentrations ofLH and FSH were also similar in immunized and control ewes, both during the late luteal phase and after ovariectomy and supplementation with oestradiol and progesterone. Numbers of ovarian follicles and corpora lutea were also unaffected by immunization. It is concluded that high endogenous concentrations of GH in sheep given food below maintenance are necessary to maintain plasma IGF-1, but do not affect the concentration of gonadotropins or ovarian follicular growth. Furthermore, rates of live-weight loss and the depression in wool growth in such animals were also independent of concentrations ofGH or IGF-1.

Keywords

reproductionsheepsomatotropinundernutritionwool
Type
Research Article
Information
Animal Science , Volume 62 , Issue 2 , April 1996 , pp. 279 - 286
Copyright
Copyright © British Society of Animal Science 1996

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References

REFERENCES

Adams, N. R., Atkinson, S. and Sanders, M. R. 1989. Effects of oestradiol implants on the ovulation rate of the ewe. Journal of Reproduction and Fertility 87: 169–174.CrossRefGoogle ScholarPubMed
Adams, N. R., Sanders, M. R., Briegel, J. R., Peter, D. W. and Rigby, R. D. G. 1996. Responses of sheep to annual cycles in nutrition. 2. Effects of diet during replenishment. Animal Science 62: 287–292.CrossRefGoogle Scholar
Armstrong, J. D., Esbenshade, K. L., Johnson, J. L., Coffey, M. T., Heimer, E., Campbell, R. M., Mowles, T. and Felix, A. 1990. Active immunization of pigs against growth hormone-releasing factor: effect on concentrations of growth hormone and insulin-like growth factor 1 journal of Animal Science 68: 427–434.CrossRefGoogle ScholarPubMed
Atkinson, S. and Adams, N. R. 1988. Adrenal glands alter the concentration of oestradiol-17β and its receptor in the uterus of ovariectomized ewes, journal of Endocrinology 375–380.CrossRefGoogle ScholarPubMed
Bagnato, A., Moretti, C., Ohnishi, J., Frajese, G. and Catt, K. 1992. Expression of the growth hormone-releasing hormone gene and its peptide product in the rat ovary. Endocrinology 130: 1097–1102.Google ScholarPubMed
Brier, B. M. and Gluckman, P. D. 1991. The regulation of postnatal growth: nutritional influences on endocrine pathways and function of the somatotrophic axis Livestock Production Science 27: 77–94.CrossRefGoogle Scholar
Brier, B. M., Gallaher, B. W. and Gluckman, P. D. 1991. Radioimmunoassay for insulin-like growth factor-1: solutions to some potential problems and pitfalls Journal of Endocrinology 128: 347–357.CrossRefGoogle Scholar
Davis, S. R., Smith, J. F. and Gluckman, P. D. 1990. Effects of growth hormone injections on ovulation rate in ewes. Reproduction, Fertility and Development 2:173–178.CrossRefGoogle ScholarPubMed
Djura, P. and Hoskinson, R. M. 1986. Radioiodination of somatostatin analogues employing Sep-Pak rapid purification and label assessment by high performance liquid chromatography. Journal of Chromatography 363: 424–427.CrossRefGoogle ScholarPubMed
Estienne, M. J., Schillo, K. K., Hileman, S. M., Green, M. A., Hayes, S. H. and Boling, J. A. 1990. Effects of free fatty acids on luteinizing hormone and growth hormone secretion in ovariectomized lambs Endocrinology 126: 1934–1940.CrossRefGoogle ScholarPubMed
Gong, J. G., Bramley, T. and Webb, R. 1991. The effect of recombinant bovine somatotropin on ovarian function in heifers: follicle populations and peripheral hormones. Biology of Reproduction 45: 941–949.CrossRefGoogle ScholarPubMed
Hart, I. C., Chadwick, P. M. E., Coert, A., James, S. and Simmonds, A. D. 1985. Effect of different growth hormone-releasing factors on the concentrations of growth hormone, insulin and metabolites in the plasma of sheep maintained in positive and negative energy balance. Journal of Endocrinology 105:113–119.CrossRefGoogle ScholarPubMed
Hua, K. M., Ord, R., Kirk, S., Li, Q. J., Hodgkinson, S. C., Spencer, G. S. G., Molan, P. C. and Bass, J. J. 1993. Regulation of plasma and tissue levels of insulin-like growth factor-1 by nutrition and treatment with growth hormone in sheep Journal of Endocrinology 136: 217–224.CrossRefGoogle ScholarPubMed
Kriel, G. V., Bryant, M. J. and Lomax, M. A. 1992. Effect of dietary protein intake and intravenous glucose infusion on plasma concentrations of insulin-like growth factor-1 in lambs. Journal of Endocrinology 132:195–199.CrossRefGoogle ScholarPubMed
MacRae, J. C., Bruce, L. A., Hovell, F. D. DeB., Hart, I. C., Inkster, J., Walker, A. and Atkinson, T. 1991. Influence of protein nutrition on the response of growing lambs to exogenous bovine growth hormone Journal of Endocrinology 130: 53–61.CrossRefGoogle ScholarPubMed
Martin, G. B., Oldham, C. M. and Lindsay, D. R. 1980. Increased plasma LH levels in seasonally anovular Merino ewes following the introduction of rams. Animal Reproduction Science 3:125–132.CrossRefGoogle Scholar
Martin, G. B., Taylor, P. L. and McNeilly, A. S. 1987. Effect of small doses of bovine follicular fluid on the tonic secretion of gonadotrophins in the ewe journal of Endocrinology 114: 73–79.CrossRefGoogle ScholarPubMed
Mesiano, S., Young, I. R., Browne, C. A. and Thorburn, G. D. 1988. Failure of acid-ethanol treatment to prevent interference by binding proteins in radioligand assays for the insulin-like growth factors Journal of Endocrinology 119: 453–460.CrossRefGoogle ScholarPubMed
Morley, F. H. W., White, D. H., Kenney, P. A. and Davis, I. F. 1978. Predicting ovulation rate from live weight in ewes Agricultural Systems 3: 27–45.CrossRefGoogle Scholar
Naar, E. M., Bartke, A., Majumdar, S. S., Buonomo, F. C., Yun, J. S. and Wagner, T. E. 1991. Fertility of transgenic female mice expressing bovine growth hormone or human growth hormone variant genes Biology of Reproduction 45: 178–187.CrossRefGoogle ScholarPubMed
Ono, M., Miki, N. and Demura, H. 1991. Effect of antiserum to rat growth hormone (GH)-releasing factor on physiological GH secretion in the female rat Endocrinology 129: 1791–1796.Google ScholarPubMed
Ryan, W. J. and Williams, I. H. 1990. Changes in the body composition of sheep fed at a maintenance level Proceedings of the Australian Society ofAnimal Production 18: 344–347.Google Scholar
Simpson, R. B., Armstrong, J. D., Harvey, R. W., Miller, D. C., Heimer, E. P. and Campbell, R. M. 1991. Effect of active immunization against growth hormone-releasing factor on growth and onset of puberty in beef heifers. Journal ofAnimal Science 69: 4914–4924.Google ScholarPubMed
Snyder, D. K., Clemmons, D. R. and Underwood, L. E. 1988. Treatment of obese, diet-restricted subjects with growth hormone for 11 weeks: effects on anabolism, lipolysis and body composition Journal of Clinical Endocrinology and Metabolism 67: 54–61.CrossRefGoogle ScholarPubMed
Suttie, J. M., Kostyo, J. L., Ebling, F. J., Wood, R. I., Bucholtz, D. C., Skottner, A., Adel, T. E., Twons, R. J. and Foster, D. L. 1991. Metabolic interfaces between growth and reproduction. IV. Chronic pulsatile administration of growth hormone and the timing of puberty in the female sheep. Endocrinology 129: 2024–2032.CrossRefGoogle Scholar
Thissen, J.-P., Underwood, L. E., Maiter, D., Maes, M., Clemmons, D. R. and Ketelslegers, J.-E. 1991. Failure of insulin-like growth factor-1 (IGF-1) infusion to promote growth in protein-restricted rats despite normalization of serum IGF-1 concentration Endocrinology 128: 885–890.CrossRefGoogle Scholar
Thomas, G. B., Cummins, J. T., Francis, H., Sudbury, A. W., McCloud, P. I. and Clarke, I. J. 1991. Effect of restricted feeding on the relationship between hypophyseal portal concentrations of growth hormone (GH)-releasing factor and somatostatin and jugular concentrations of GH i n ovariectomized ewes. Endocrinology 128: 1151–1158.CrossRefGoogle Scholar
Waghorn, G. C., Flux, D. S. and Ulyatt, M. J. 1987. Effects of dietary protein and energy intakes on growth hormone, insulin, glucose tolerance and fatty acid synthesis in young wether sheep Animal Production 44: 143–152.Google Scholar
Wheaton, J. E., Al-Raheem, S. N., Massri, Y. G. and Marcek, J. M. 1986. Twenty-four-hour growth hormone profiles in Angus steers. Journal of Animal Science 62: 1267–1272.CrossRefGoogle ScholarPubMed
Wynn, P. C., Wallace, A. L. C., Kirby, A. C. and Annison, E. F. 1988. Effects of growth hormone administration on wool growth in merino sheep. Australian Journal of Biological Sciences 41:177–187.CrossRefGoogle ScholarPubMed